Vacuum mold for molding concrete and the like



June 28, 1949. K. P. BILLNER 2,474,721

VACUUM MOLD FOR MOLDING CONCRETE AND THE LIKE 2 Sheets-Sheet 1 Filed March 1., 1946 INVENTOR F434, 1? Ema/vise,

ATTO RN EY June 28, 1949. p, BILLNER 2,474,721

VACUUM MOLD FOR MOLDING CONCRETE AND THE LIKE Filed March 1, 1946 1 2 Sheets-Sheet 2 6105s (2011/ j M M05 $065M INV ENTOR A7164, R BILL/V68,

ATTORNEY vehicle .fromnewly laid concrete.

Patented June 28, 1949 VACUUM MOLDFOR MOLDING CONCRETE I AND THE LIKE l s .Karl r. Billner l'hiladelphla, rs; assignor to Vacuum Concrete 'Inc., a corporation of Penn? sylvfaula Application March X 14c1aiins.

The erection of forms for molding plastic bodies, particularly concrete, has always represented .a major portion of the expense experienced with concrete structures. Ordinarily, forms are constructed, the concreteis poured, and after a substantial time, depending upon climatic conditions, the forms aregtorn down. and for the most part, discarded. l l l t On July fl, 1936, the present inventor received LettersPatent 2,056,867 relating to the use of subatmospheric pressures to remove the excess As described in the patent, and contemplated herein, excess vehicle refers to thatfportion used to obtain sufficient plasticity for molding, but unnecessary for completion of the setting reaction. Forms of the type disclosed in the=patent referred to, have been mechanically joined as disclosed in a later patent to the same inventor numbered 2,116,557, dated May 10, 1938, to define opposed form surfaces to receive the plastic mix to be molded.

It is with a view towards eliminating thenecessity for. any appreciable mechanical manipulaties is contemplated only in the event that high walls or similar constructions are being produced, and even under these circumstances, ties will be required only adjacent the top of. the form elements.

Forms in accordance with the presentinven- .tion for use with moldable plastic bodies are provided with means for securing them to a support, which means is responsive to subatmospheric pressure to accomplish this result. The means may comprisea sealing member for engagement with the supportand connections with one or more sources of subatmospheric pressure. The sealing member may comprise a relatively flex- 1, 1946, Serial No. 651,351

ments for contact with the materialbeingmolded. Such a. perforate surface or surfaces may likewise communicate with asource of subatmospheric pressure so. that when the form members are in position and the body poured,excess vehicle, -which may be water, will be removed through such perforate surfaces. 1 1

The supporting surface to which the forms are secured may be vertical, horizontal, or at, any other desired angle, so long as thesecuring means defines therewith a chamber or chambers closed .tion of. the forms between molding operations ible lip (portion whichwill respond rapidly to the differential of atmospheric pressure externally of the securing means and reduced pressure internally thereof. The sealing means may also comprise a readily deformable sealing element of rubber or similar material to permit the forms to move to their operative positions. .Suitable stops may be provided tolimit theforms to such operative positions. l

Where it is desired to extract or removeexcess vehicle from the moldable plastic body, a perforate surface may be provided. for the form eleing of walls. slabs, trusses, beams, and a large variety of other structures'and structural elements as will be clear to those skilled in the art after reference to a more detailed description of the invention with reference to the accompanying drawings wherein: l l

Fig. 1 is a fragmentary elevation of apparatus for forming a roof truss in accordance with the present invention; l i

Fig. 2 is a. section of the apparatus taken along line 2-2 of Fig. 1;

Fi 3 is a sectional elevation of another form of apparatusembodying the present invention; and

Fig. 4 is a sectional elevation of another modification.

With reference to Figs. 1 and 2, a suitable support I0 is provided for the forms I2, each of which is shown as having a nipple for connection with a suitable source of subatmospheric pressure through hose lines It which communicate bymeans of suitable nipples l 8 with a manifold 20. and pipe line 22 in which a suitable valve 24 is providedfor connection and disconnection of the line with a suction pump not shown; A nipple 26 projecting from the central structure ofthe apparatus is connected through hose line 28 and valve. 30 with the manifold 20 and the source of. subatmospheric pressure. As shown in Fig. 2, a base plate 32 is received upon the support l0 upon which issuperimposed a pedestal 34 of suitable material, indicated as being of concrete, containing a plurality of transverse tubular elements 36 extending therethrough and an axial tubular header 38 in communication with the nipple 26, embedded near the upper portion of the pedestal. Surmounting the pedestal there is provided a. form element III defining the lower surface of the form proper, its upper perforate surface being defined by, for example, one or more layers of foraminous material 42 such as screening or hardware cloth upon which is superimposed a layer of fabric 44 such as woven glass cloth. The perforate surface so formed communicates with the header 38 through a suitable number of passages 46 formed through the form element 40.

The form elements l2, shown in Fig. 2-in their extended relationship with respect to the pedestal, are provided with flexible resilient gaskets 46 .of soft rubber or similar material whichmay be suitably fastened by means of adhesive or otherwise to the pedestal and/or form elements I2 at either side of the transverse tubularelements 66 to define vacuum chambers 60 which are maintained in communication with one another through the transverse tubular members 66.

When suction is applied to the vacuum chambers 50 through one or both nipples l4,'the form elements l2 will be forced towards the pedestal by the difference between atmospheric pressure acting externally of the form elements and the subatmospheric pressure produced within the vacuum chambers. The yieldable gaskets 46 will become deformed until the inner surfaces of the form elements 12 engage the edges of the plate 32 and the form element 40, whereupon the form elements l2 will assume the positions indicated in broken lines to define a mold with the form element! ready for reception of the moldable plastic body. After the moldable plastic body containing excess vehicle such as a concrete mix containing excess water is introduced into the .mold cavity 52 thus formed, the header 661 will be placed in communication with a source of subatmospheric pressure through the nipple 26, hose 28, valve 30, manifold 20, valve 24 and hose line 22 to extract such excess vehicle from the plastic mix through the perforate surface of the form element 40 and passages 46;. After'the molding operation has been completed and excess vehicle extracted from the mix, the molded body will become sufiiciently self sustaining after a predetermined time to permit its removal from the form. The header 38 will be disconnected from the source of subatmospheric-pressure by manipulation of the valve arrangement and subatmospheric pressure will likewise be disconnected from the vacuum chambers 50 in a similar" manner.

ments when vacuum is applied to the chambers 62 through the nipples 64 to deform the gaskets and move the side fonns towards the rigid form as the result of the differential pressure between atmosphere acting externally and the subatmospheric pressure within the chambers.

The upper portions of the side forms are provided with perforate surfaces formed of one or more layers of foraminous material 68 of screening, hardware cloth or the like surfaced with such material as woven glass fabric ll for direct contact with the bodyto be molded. These perforate surfacesare placed in communication with one The resiliency of the gaskets 48 will bias them outwardly to the full line position shown in Fig. 2

rendering the molded body accessible for removal by suitable lifting means.

' With reference to Fig. 3, the apparatus is depicted for forming beams or the like suitable for the construction of a bridge deck. The support It has mounted thereon a rigid form element 64 whose upper surface complements a channel. The element is provided with vertical walls 66 for cooperation with vertical form elements 66 releasably secured thereto by means of subatmospheric pressure.

The lower portions of the side forms 66 are provided with flexible resilient spaced gaskets 66 of soft rubber or like material for application to the lower vertical portion of the rigid form element 54, defining therewith and with the lower wall portion of the side form elements, vacuum chambers 62 which are placed in communication with one or more sources of subatmospheric pressure, not shown, through suitable nipples 64. Positioning plates 66 areprovided at the upper and lower edges of the vertical wall portion-of the rigid form to properly locate the side form ele' to facilitate its removal.

or more sources of subatmospheric pressure through a suitable number of nipples 12 connected with, such a source of subatmospheric pressure, not shown, when it is desired to extract excess vehicle: from the plastic mix. To impart the desired configuration to themolded body, the form elements may be provided with projections or indentations of the type exemplified by the projections 14 formed internally on the side forms 56. i i a After the material to be molded has been in- I troduced into the cavity I6 defined by the upper surface of the rigid form element and the inner vertical surface of the side form elements, the nipples 12 may be connected with a suitable vacuum pump, not shown, and suction applied until the desired quantity of excess vehicle has been removed. Then the source of suction-can be disconnected from the nipples I2 and from the nipples 64 permitting the side form elements to move horizontally from contact with the molded body The support III in Fig. 4 is depicted as receiving a pair of vertical form elements I6 provided with layers of foraminous material 66 of screen or the like over which are applied layers of woven glass ,or similar fabric 62 for contact with the plastic body to be molded. Communication with the perforate surface thus formed with a suitable source of subatmospheric pressure not shown is established through nipples 84 penetrating the walls of the form elements. Suitably secured to the base of each of theseform elements there is a flange 6 6 spaced from the support I! by soft yieldable resilient gaskets 66 of rubber or-similar material, the outer of which is provided with a thin lip 90 of sheet rubber or the like to facilitate rapid and positivesealing engagement with the support. Each of the vacuum chambers 62 defined by the flange 86, its spaced gaskets 66 and the surface of the support is connected with a source of subatmospheric pressure not shown through suitable nipples 64.

It will thus follow that when it is desired to position the form elements upon the support, suction will be applied to the nipples 94 whereupon atmospheric pressure will force the flanges and their gaskets downwardly upon the support securing them together, following which the plastic material will be introduced into the cavity 96 to the desired height, whereupon the nipples. 64 will be placed in communication. with a source of subatmospheric pressure to extract the excess vehicle from the plastic mix. As soon as the molded body becomes self sustaining the various nipples can be disconnected from the source of subatmosphericpressure and the forms readily removed to enable them to be used in amples are particularly high; it may become necessaryto tie the upper ends together during the molding operation to prevention any tendency which theymay have to separate due to the weight of the plastic material contained there-- between. The parts willbe designed structurally to sustain the loads imposed upon them in a manner withwhich those skilled in the artwill be conversant.

The foregoing illustrations and the description accompanying them represent a few of the contemplated applications of a the present invention andthey are not tobe construed as restrictive beyond the scope of the appended claims.

1. A form element for use with a, moldable plastic body containingexcess vehicle, said form element having a pervious surface for engagement with said bod related fluid actuated means forsecuring said element to a support, said means ,ment with said body, related fluid actuated means for securing said 'element to a support, said means comprising a sealing member for engagement with said support to form achamber therewith, and connecting means for communicating said porous surfaceand sealing member with a source of subatmospheric pressure to reduce the pressure within such chamber to position said element with respect to said support and remove excess water through said surface from said body, and pressure control means for actuating said securing means exclusively of the removal of excess water.

3.'A separable form for use with a concrete mix containing excess water, said form having pervious surfaces for engagement with said mix, related fluid actuated means for securing said form to a support, said means comprising a sealing member for each separable part for engagement with said support, and connecting means for communicating said surfaces and sealing members with a source of subatmospheric pressure to position said form with respect to said support and remove excess water through said surfaces from said mix, and pressure control means for actuating said securin means exclusively of the removal of excess water.

4. A form for use with a moldable plastic body which imposes a hydrostatic force thereon, related fluid actuated means for securing said form to a support, said means comprising a sealing member for engagement with said support and means for connecting said securing means with a source of subatmospheric pressure for producing a reducedpressure between said sealing member and support, said sealing member having an effective area exceeding that required by the dimensions of said form to secure proximate portions of said form to said support by subatmospheric pressure, the excess area being sufficient to secure the form against hydrostatic ifnorce imposed by said body in its plastic condi- 5. A form for use with a moldable plastic body which imposes a hydrostatic force thereon, ,re-r lated fluid actuated means for securing said form to a support, said means comprising a resilient sealing member for engagement with said support and means for connecting said securing means with a source of subatmospheric pressure for producing a reduced pressure between said sealing member and support, said sealing member having an effective area exceeding thatrequired by the dimensions of said form to secure proximate portions of said form to said support by subatmospheric pressure, the excess area being suilicientto secure the form against hydrostatic force imposed by said body in its plastic 6. A form for use with a moldable concrete body which imposes a hydrostatic force thereon, related fluid actuated means for securing said form to a support,said means comprising a yieldable sealing member for engagement with said support to define a chamber therewith and means for connecting said securing means with a source of subatmospheric pressure to reduce the pressure in such chamber, said sealing member having an effective area exceeding that required by the dimensions of said form to secure proximate portions of said form to. said support by subatmospheric pressure, the excess area being suflicient to secure the form against hydrostatic force imposed by said body in its plastic condition.

71 A separableform for use with a moldable plastic body which imposes a hydrostatic force thereon, related fluid actuated means for securing separable parts of said form to a support, said means comprising a sealing member carried by each part for engagement with said support and means for connecting said securing means with a source of subatmospheric pressure for producing a reduced pressure between said sealing members and support, each sealing member having an effective area exceeding that-required by the dimensions of said form part to secure proximate portions of said form to said support by subatmospheric pressure, the excess area being sufficient to secure the form part against hydrostatic force imposed by said body in its plastic condition.

8. A form having a perforate surface for use with a moldable plastic body containing excess vehicle, related fluid actuated means for securing said form to a support, said means comprising a sealing member for engagement with said support and means for connecting said securing means and sealing member in communication with a source of subatmospheric pressure. said sealing member having an effective area exceed-- ing that required by the dimensions of said form to secure proximate portions of said form to said support by subatmospheric pressure, the excess area being suflicient to secure the form against hydrostatic force imposed by said body in its plastic condition.

9. A form having a perforate surface for use with a concrete mix containing excess water, related fluid actuated means for securing said form to a support, said means comprising a seal ing member for engagement with said support, means for connecting said surface with a source of subatmospheric pressure to remove excess water'from said body, means for connecting said securing means with a source of subatmospheric pressure for producing a reduced pressure between said sealing member and support, and pressure control means for actuating said securing means exclusively of the application of pressure to said surface.

10. A form having a perforate surface portion for removing excess vehicle from a moldable plastic body which imposes a hydrostatic force thereon, a related fluid actuated sealing portion for application to a support, and means for connecting said sealing portion with a source of subatmospheric pressure for positioning said perforate surface portion with respect to said support, said sealing portion having an eflective area exceeding that required by the dimensions of said form to secure proximate portions of said form to said support, by subatmospheric pressure, the excess area being suflicient to secure the form against hydrostatic forces imposed by said body in its plastic condition. v

11. A form having a perforate surface portion for removing excess vehicle from a moldable plastic body which imposes a hydrostatic force thereon, a related fluid actuated sealing portion 7 adapted to define a closed chamber with respect to a support, and means for connecting said sealing portion with a source of subatmospheric pres-' sure for positioning said perforate surface portion with respect to said support, said sealing portion having an efiective area exceeding that required by the dimensions of said form to secure proximate portions of said form to said support by subatmospheric pressure, the excess area being suiflcient to secure the form against hydrostatic forces imposed by said body in its plastic condition.

12. A form having a perforate surface portion for removing excess vehicle from a moldable plastic body, a related fluid actuated sealing portion adapted to define a closed chamber with respect Number."

to a support, means for connecting said sealing portion and said perforate portion with a source of subatmospheric pressure for positioning said form in an operating position and removing excess vehicle through said'surface portion from said body, and pressure'control means for applying pressure to said chamber exclusively of the application of pressure to said perforate portion. a

13. A form having-a perforate surface portion for removing excess water from a concrete body, a fluid actuatedvsealing portion for application to a support adjacent said body, means for connecting said portions with subatmospheric pressure to position said form in an operating position and remove excess water through said surface portion from said body and independently operable pressure control devices for said portions.

14. A form having a perforate. surface portion for removing excess vehicle from a moldable plastic body, related 'fluid actuated sealing means responsive to subatmospheric pressure for securing said form to a support adjacent to said body, means for connecting said surface portion with a source of subatmospheric pressure for removing excess vehicle through said surface portion from said body and independently operable pressure control means for said sealing means.

KARL P. BILLNER.

REFERENCES CITED The following referenlces are of record in the file of this patent:

UNITED STATES PATENTS Name Date 2,11 .55: Billner May 10, 1938 

